JP2009266535A - Overcurrent tripping mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an overcurrent tripping mechanism with the small number of components which helps motion of a bimetal by biasing force to bending the bimetal by flow of overcurrent and to push a bargaining piece in a releasing direction and provides uniform duration until interrupting an electric circuit. <P>SOLUTION: The overcurrent tripping mechanism disposed in a case of a circuit breaker is composed of: the bargaining piece of which the position is retained by a spring and an arm portion according to a handle portion during energization; and the bimetal which pushes and drives the bargaining piece as well as includes a first end that is fixed and a second end that is freely disposed, and the bimetal includes a biasing structure. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an overcurrent tripping mechanism in a circuit breaker.

Conventionally, in a circuit breaker using an overcurrent tripping mechanism, as described in Patent Document 1, when an abnormality such as an overcurrent, a short circuit, or a leakage occurs in a main circuit, a bimetal 35 provided inside the case The tripping mechanism composed of the engagement piece 34 is driven to release the pressing to the movable contact by the opening / closing mechanism, and the main circuit is cut off by separating the movable contact from the fixed contact by the spring. There was a circuit breaker.
JP 2004-55173 A

  However, in the invention described in Patent Document 1, the bimetal is bent when an overcurrent flows, and the engaging piece is pressed in the release direction, but the force by which the bimetal attempts to press the engaging piece is not transmitted well to the engaging piece. There is a drawback that the engaging piece may not operate normally. Thereby, there exists a fault that the time until a latching piece interrupts | blocks an electric circuit becomes non-constant. Further, in order to solve this, it is conceivable to weaken the force for holding the engaging piece, but there is a drawback that the time until the electric circuit is cut off may be too short.

  For this reason, the problem to be solved by the present invention is that the overcurrent flows, the bimetal is bent, and the force to try to press the engaging piece in the release direction is urged to help the operation of the bimetal, and the electric circuit is interrupted. To provide an overcurrent tripping mechanism with a constant number of parts required until a certain number of parts is obtained.

  The overcurrent tripping mechanism of the present invention made to solve the above-described problem is an overcurrent tripping mechanism provided inside the case of a circuit breaker, and this overcurrent tripping mechanism is a spring when energized. It consists of a latching piece whose position is held by the arm part related to the handle part, and a bimetal that presses and drives the latching piece, fixes one end, and freely provides the other end. An overcurrent tripping mechanism characterized by that.

  According to the overcurrent tripping mechanism of the present invention, by providing the bimetal with an urging structure, it is possible to assist the force with which the bimetal presses the engaging piece. As a result, it is possible to obtain a constant time until the force by which the bimetal attempts to press the engaging piece is normally transmitted and the electric circuit is cut off.

  In the present invention, a structure capable of obtaining a constant time until interruption of the electric circuit is made possible with a small number of processing.

Embodiments of the present invention will be described below.
An overcurrent tripping mechanism provided inside a case of a circuit breaker, and this overcurrent tripping mechanism is held in position by springs 1 and 11 and arm portions 3 and 13 associated with a handle portion 2 when energized. And the bimetals 5 and 15 are configured to press and drive the latching pieces 4 and 14 and fix one end and freely provide the other end, and one end of the bimetals 5 and 15 provided freely. The upper bending portions 7 and 17 were provided by bending the upper portion of the plate. By dividing the entire length of the bimetal 5 and 15 up to the hooking pieces 4 and 14, the long part is made the long side parts 6 and 16, and the short part is made the upper bending parts 7 and 17. It is possible to avoid this. Thereby, when the bimetals 5 and 15 press the engaging pieces 4 and 14, the force of the bimetals 5 and 15 is not transmitted well, and the engaging pieces 4 and 14 do not operate normally, and the time until the electric circuit is interrupted varies. It is possible to reduce the risk of getting out.

  An overcurrent tripping mechanism provided inside the case of the circuit breaker, and this overcurrent tripping mechanism includes an engaging piece 24 that is held in position by a spring 21 and an arm portion 23 associated with the handle portion when energized. , The engagement piece 24 is driven and pressed, and one end is fixed, and the other end is freely provided. The bimetal 25 is freely provided. Was provided. By dividing the entire length of the bimetal 25 up to the hooking piece 24, the long part is the long side part 26, and the short part is the lateral bending part 27, so that the short part can be prevented from bending. It is. Thereby, when the bimetal 25 presses the engagement piece 24, the force of the bimetal 25 is not transmitted well, and the engagement piece 24 does not operate normally, and it is possible to reduce the possibility that the time until the electric circuit is interrupted varies. It is.

  As described above, the overcurrent tripping mechanism of the present invention is configured to normally cut off the electric circuit in a row when an overcurrent flows by providing a biasing structure that promotes bending in the bimetal. is there.

It is sectional drawing of the overcurrent tripping mechanism in Example 1 of this invention. It is an expanded sectional view of the A section of the overcurrent tripping mechanism in Embodiment 1 of the present invention. It is a partial expanded sectional view of an overcurrent trip mechanism in Example 2 of the present invention. It is sectional drawing of the overcurrent trip mechanism of patent document 1 in a prior art.

Explanation of symbols

1, 11, 21 Spring 2, 12, 22 Handle part 3, 13, 23 Arm part 4, 14, 24, 34 Engagement piece 5, 15, 25, 35 Bimetal 6, 16, 26 Long side part 7, 17 Bending Part 28 Lateral bending part

Claims (1)

  An overcurrent tripping mechanism provided inside a case of a circuit breaker, wherein the overcurrent tripping mechanism has a latching piece whose position is held by a spring and an arm portion related to a handle portion when energized, and the latching An overcurrent tripping mechanism comprising a bimetal having one end fixed and one end fixed, and the other end freely provided, and a biasing structure provided on the bimetal.

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